My cousin Ruby showed me how to dive for rocks (she's so good at it she can can stay underwater forever and bring up rocks the size of my head), so I thought I'd share how to do it with everyone.
STEP 1: Find a nice tidal pool and give Mom your best puppy face.
STEP 2: Bark at Mom to tell her to stop playing with her camera, and to hurry up and throw you a rock (if necessary).
STEP 3: Find the rock with your foot.
STEP 4: Dive underwater and pick up the rock.
STEP 5: Bring the rock back to Mom so she can throw it again. (It might not be the same rock but that's okay.)
And here's Ruby, the ultimate water dog.